Some free software passes your information on to advertisers, changes your PC or downloads other software without asking you. Some suppliers will claim that this is OK because you agreed to this. How? People often click on the “agree” button to accept 20 pages. But buried in the middle can be a sentence allowing the software to do whatever it likes. You can argue in court that the terms aren’t reasonable, but then it will be too late — the damage has been done and your PC is broken. Learn from other people’s pain: if terms and conditions are hard to understand, it is probably deliberate. If it isn’t worth the trouble to read the conditions, don’t risk using the software.